Severe weather such as tornadoes and hail pose substantial public safety hazards and are the source of substantial financial losses each year. While there are a wide variety of automated methods for detecting tornadoes and hail using traditional single-polarization (“single-pol”) weather radars, the use of dual-polarization (“dual-pol”) radar data can substantially improve upon existing methods. In particular, debris lofted by tornadoes and hail cores often have distinct signatures in dual-pol radar data. Though the signatures of these severe weather events are distinct, there is a lack of automated detection systems for identifying them.
Particularly lacking in the current art is the ability to determine if a tornado visible on radar has actually touched down on the ground. While traditional single-pol radars can provide strong evidence for the presence of tornadoes, it can be very difficult to determine if a given storm has spawned a tornado that is actually causing damage on the ground. Moreover, when a tornado is rain-wrapped or during a nighttime storm, spotters on the ground may not be able to provide visual confirmation of a tornado on the ground. In some cases, “debris balls”, regions containing debris lofted by tornadoes, can be seen in single pol reflectivity. However, it can be difficult to distinguish what might be a debris ball in rain-wrapped tornadoes or in tornadoes embedding in a line of storms. Dual-pol radars, on the other hand, provide a much more finely detailed view of the shapes and amounts of lofted material, resulting in a much clearer picture of a tornado debris signature (“TDS”). The presence of a TDS in dual-polarization radar data is strong indication that there is a tornado on the ground. The present disclosure provides an improved method of detecting, classifying and determining the location of a TDS.